This invention relates to a steering wheel
To impart steering wheels a high-quality appearance, it is known to provide the steering wheel rim with decorative elements having special surfaces, e.g. wood, aluminum or carbon fiber. Such decorative elements are often combined with a leather coating of the steering wheel rim.
A steering wheel with such decorative elements is described for instance in DE 298 03 133 U1. Seen in cross-section, the decorative element used there extends across an angle of about 90xc2x0 in peripheral direction of the steering wheel rim. Via a latching connection it is connected with a component anchored in the sheathing of the steering wheel skeleton. This construction requires a complex injection coating tool for making the sheathing.
Furthermore, it is known to surround a steering wheel skeleton with a sheathing and in turn provide this sheathing with an externally fabricated shell.
It is the object of the present invention to provide a steering wheel with decorative elements in a simple, inexpensive and flexible way.
This object is solved in a steering wheel which comprises a steering wheel rim, a hub and at least one spoke connecting the steering wheel rim and the hub. At least one of the steering wheel rim and the spoke comprises a skeleton, a sheathing surrounding the skeleton as well as a shell arranged around the sheathing, and at least one decorative element. At least one latching element is provided by means of which the decorative element is directly attached to the shell. Since the decorative element is attached to the shell and is not fixed in the sheathing, the injection molding tool for the sheathing can be designed much simpler than in accordance with the cited prior art. The latching connection with the shell also offers the advantage that the decorative element can be produced in a less expensive way and with a relatively small inherent stability, as feel and strength of the steering wheel rim or the spoke are determined by the shell. The use of a shell surrounding the sheathing of the skeleton provides for a modular construction of the steering wheel and thus facilitates changes in the design, as there must only be changed the tool for the shell, which can be produced independently of the rest of the steering wheel, in order to achieve a variation in the number, size or arrangement of the decorative elements. A latching connection provides a fast and safe method for fastening the decorative element. Since the decorative element need not perform the function of the shell at the point where it is seated, a relatively small inherent weight is sufficient. A latching connection therefore is sufficient for the occurring loads, also for vibrations.
In the shell, preferably one opening or, in more general terms, one cut-out is provided, into which protrudes the latching element for latching the decorative element with the shell. Manufacturing an opening or cut-out in the shell represents no problem in terms of injection molding technology. Openings with a small cross-section are sufficient for fastening a decorative element.
In an advantageous embodiment of the invention, the latching element protrudes through the opening and engages behind the shell. This is a simple, inexpensive and stable method of fastening the decorative element. A further advantage consists in that the latching element of the decorative element can be designed so as to be very simple.
Preferably, the sheathing has a recess, into which the latching element extends. To facilitate engaging behind the shell, a recess should favorably be provided at the corresponding point in the sheathing. In terms of manufacturing technology, this can be achieved by a simple modification of the tool.
Advantageously, the shell completely surrounds the skeleton in peripheral direction seen in a cross-section of the steering wheel rim and the spoke, respectively. Thus, both the desired diameter of the steering wheel rim or of the spoke and the general feel can be predetermined by the diameter and material of the shell. Further, the decorative element radially adjoins the shell (seen in a cross-section of the steering wheel rim and the spoke, respectively) so that the decorative element defines a second, outer shell. This design leads to an improved fix position of the decorative element.
Preferably, the shell consists of an upper shell and a lower shell, the shells having edges at which they are connected with each other. This provides for an increase in flexibility of the modular construction of the steering wheel, as for instance the lower shell can remain the same for all types of steering wheel, whereas the upper shell is adapted to the respective design. This is true above all when upper shell and lower shell are connected with each other by a latching connection. In this way, a modular construction of the steering wheel is obtained, in which different shell elements and decorative elements need only be plugged onto a base body consisting of the skeleton and the sheathing. Thus, the arrangement, number and size of the decorative elements can be designed very flexibly.
Favorably, the decorative element is directly supported on the shell on the outer side thereof, as in this case the decorative element itself must have no very high inherent stability, because it is supported by the shell. This renders the manufacture of the decorative element less expensive.
In one embodiment of the invention, there is provided a leather coating which has edges and surrounds the shell, and it is provided that the edges of the leather coating are at least partly clamped between the decorative element and the shell. In the region of the decorative element it is therefore not necessary to fix the leather coating by sewing or bonding, as it can be attached by clamping via the decorative element.
Preferably, the latching element is integrally molded on the decorative element, which provides for an inexpensive manufacture. However, the decorative element can also consist of a carrier, at which the latching element is molded, and of a decorative surface, e.g. of wood veneer, imitated wood, aluminum or some other material. For metal surfaces, the decorative element can also be made completely of metal.
Of course, there may also be provided several decorative elements at one steering wheel, and the decorative elements may be disposed both at the steering wheel rim and at the steering wheel spokes.
It is also conceivable to design the latching element of the decorative element for instance as a recess in the decorative element and provide for instance a projection or a latching hook on the shell.